<template>
  <div class="water-eval-container">
    <div class="container" :style="{ marginLeft: left + 'px' }">
      <div class="child">
        <div class="top" :style="{ visibility: active ? 'visible': 'hidden'}">
          <div class="number">{{ percent }}</div>
          <div class="unit">%</div>
        </div>
        <div class="bottom">{{ bottomText }}</div>
      </div>
    </div>
    <div ref="piechart" class="cityGreenLand-charts" />
  </div>
</template>

<script>
import * as echarts from 'echarts';
import 'echarts-gl';
export default {
  name: 'PieChart3D',
  components: {},
  props: {
    optionData: Array,
    isActive: {
      type: Boolean,
      default: false
    },
    index: Number,
    change: Boolean,
    text: String
  },
  data() {
    return {
      percent: 0,
      chart: null,
      active: false,
      option: null,
      selectedIndex: '',
      left: 0,
      // 总数
      total: 0,
      topNum: 0,
      bottomText: this.text
    };
  },
  watch: {
    change: function() {
      this.monitorClick();
    },
    optionData() {
      this.calculateTotal();
      this.active = false;
      this.option = this.getPie3D(this.optionData, 0.86);
      this.chart.setOption(this.option);
    }
  },
  created() {
    this.calculateTotal();
  },
  mounted() {
    this.$nextTick(function() {
      this.left = this.$refs.piechart.clientWidth / 2;
      this.init();
      // this.changePercent();
      this.monitorClick();
    });
  },
  methods: {
    init() {
      // 构建3d饼状图
      this.chart = echarts.init(this.$refs.piechart);
      // 传入数据生成 option
      this.option = this.getPie3D(this.optionData, 0.86);
      this.chart.setOption(this.option);
      this.bindListen(this.chart);
    },

    getPie3D(pieData, internalDiameterRatio) {
      // internalDiameterRatio:透明的空心占比
      const that = this;
      const series = [];
      let sumValue = 0;
      let startValue = 0;
      let endValue = 0;
      let legendData = [];
      let legendBfb = [];
      const k = 1 - internalDiameterRatio;
      // pieData.sort((a, b) => {
      //   return b.value - a.value;
      // });
      // 为每一个饼图数据，生成一个 series-surface 配置
      for (let i = 0; i < pieData.length; i++) {
        sumValue += pieData[i].y;
        const seriesItem = {
          name:
            typeof pieData[i].x === 'undefined'
              ? `series${i}`
              : pieData[i].x,
          type: 'surface',
          parametric: true,
          wireframe: {
            show: false
          },
          pieData: pieData[i],
          pieStatus: {
            selected: false,
            hovered: false,
            k: k
          },
          center: ['10%', '50%']
        };

        if (typeof pieData[i].itemStyle !== 'undefined') {
          const itemStyle = {};
          typeof pieData[i].itemStyle.color !== 'undefined'
            ? (itemStyle.color = pieData[i].itemStyle.color)
            : null;
          pieData[i].itemStyle.opacity = 0.6;
          typeof pieData[i].itemStyle.opacity !== 'undefined'
            ? (itemStyle.opacity = pieData[i].itemStyle.opacity)
            : null;
          seriesItem.itemStyle = itemStyle;
        }
        series.push(seriesItem);
      }

      // 使用上一次遍历时，计算出的数据和 sumValue，调用 getParametricEquation 函数，
      // 向每个 series-surface 传入不同的参数方程 series-surface.parametricEquation，也就是实现每一个扇形。
      legendData = [];
      legendBfb = [];
      for (let i = 0; i < series.length; i++) {
        endValue = startValue + series[i].pieData.y;
        series[i].pieData.startRatio = startValue / sumValue;
        series[i].pieData.endRatio = endValue / sumValue;
        series[i].parametricEquation = this.getParametricEquation(
          series[i].pieData.startRatio,
          series[i].pieData.endRatio,
          false,
          false,
          k,
          series[i].pieData.y
        );
        startValue = endValue;
        const bfb = that.fomatFloat(series[i].pieData.y / sumValue, 4);
        legendData.push({
          name: series[i].name,
          value: bfb
        });
        legendBfb.push({
          name: series[i].name,
          value: bfb
        });
      }
      const boxHeight = this.getHeight3D(series, 17); // 通过传参设定3d饼/环的高度，26代表26px
      // 准备待返回的配置项，把准备好的 legendData、series 传入。
      const option = {
        xAxis3D: {
          min: -1,
          max: 1
        },
        yAxis3D: {
          min: -1,
          max: 1
        },
        zAxis3D: {
          min: -1.5,
          max: 1
        },
        grid3D: {
          show: false,
          boxHeight: boxHeight, // 圆环的高度
          viewControl: {
            // 3d效果可以放大、旋转等，请自己去查看官方配置
            alpha: 30, // 角度
            beta: 100,
            distance: 120, // 调整视角到主体的距离，类似调整zoom
            rotateSensitivity: 0, // 设置为0无法旋转
            zoomSensitivity: 0, // 设置为0无法缩放
            panSensitivity: 0, // 设置为0无法平移
            autoRotate: false // 自动旋转
          }
        },
        series: series
      };
      return option;
    },

    // 获取3d丙图的最高扇区的高度
    getHeight3D(series, height) {
      // series.sort((a, b) => {
      //   return b.pieData.value - a.pieData.value;
      // });
      return (height * 15) / 250;
    },

    // 生成扇形的曲面参数方程，用于 series-surface.parametricEquation
    getParametricEquation(startRatio, endRatio, isSelected, isHovered, k) {
      // 计算
      // const midRatio = (startRatio + endRatio) / 2;
      const startRadian = startRatio * Math.PI * 2;
      const endRadian = endRatio * Math.PI * 2;
      const height = isSelected ? 60 : 25;
      // const midRadian = midRatio * Math.PI * 2;
      // 如果只有一个扇形，则不实现选中效果。
      if (startRatio === 0 && endRatio === 1) {
        isSelected = false;
      }
      // 通过扇形内径/外径的值，换算出辅助参数 k（默认值 1/3）
      k = typeof k !== 'undefined' ? k : 1 / 3;
      // 计算选中效果分别在 x 轴、y 轴方向上的位移（未选中，则位移均为 0）
      const offsetX = 0;
      const offsetY = 0;
      // 计算高亮效果的放大比例（未高亮，则比例为 1）
      const hoverRate = isHovered ? 1.05 : 1;
      // 返回曲面参数方程
      return {
        u: {
          min: -Math.PI,
          max: Math.PI * 3,
          step: Math.PI / 32
        },
        v: {
          min: 0,
          max: Math.PI * 2,
          step: Math.PI / 20
        },
        x: function(u, v) {
          if (u < startRadian) {
            return (
              offsetX +
              Math.cos(startRadian) * (1 + Math.cos(v) * k) * hoverRate
            );
          }
          if (u > endRadian) {
            return (
              offsetX + Math.cos(endRadian) * (1 + Math.cos(v) * k) * hoverRate
            );
          }
          return offsetX + Math.cos(u) * (1 + Math.cos(v) * k) * hoverRate;
        },
        y: function(u, v) {
          if (u < startRadian) {
            return (
              offsetY +
              Math.sin(startRadian) * (1 + Math.cos(v) * k) * hoverRate
            );
          }
          if (u > endRadian) {
            return (
              offsetY + Math.sin(endRadian) * (1 + Math.cos(v) * k) * hoverRate
            );
          }
          return offsetY + Math.sin(u) * (1 + Math.cos(v) * k) * hoverRate;
        },
        z: function(u, v) {
          if (u < -Math.PI * 0.5) {
            return Math.sin(u);
          }
          if (u > Math.PI * 2.5) {
            return Math.sin(u);
          }
          return Math.sin(v) > 0 ? height : -15;
        }
      };
    },

    fomatFloat(num, n) {
      var f = parseFloat(num);
      if (isNaN(f)) {
        return false;
      }
      f = Math.round(num * Math.pow(10, n)) / Math.pow(10, n); // n 幂
      var s = f.toString();
      var rs = s.indexOf('.');
      // 判定如果是整数，增加小数点再补0
      if (rs < 0) {
        rs = s.length;
        s += '.';
      }
      while (s.length <= rs + n) {
        s += '0';
      }
      return s;
    },

    bindListen(myChart) {
      // 监听鼠标事件，实现饼图选中效果（单选），近似实现高亮（放大）效果。
      const that = this;
      let hoveredIndex = '';
      // 监听点击事件，实现选中效果（单选）
      myChart.on('click', function(params) {
        // 从 option.series 中读取重新渲染扇形所需的参数，将是否选中取反。
        const isSelected = !that.option.series[params.seriesIndex].pieStatus
          .selected;
        const isHovered =
          that.option.series[params.seriesIndex].pieStatus.hovered;
        const k = that.option.series[params.seriesIndex].pieStatus.k;
        const startRatio =
          that.option.series[params.seriesIndex].pieData.startRatio;
        const endRatio =
          that.option.series[params.seriesIndex].pieData.endRatio;
        // 如果之前选中过其他扇形，将其取消选中（对 option 更新）
        if (that.selectedIndex !== '' && that.selectedIndex !== params.seriesIndex) {
          that.option.series[
            that.selectedIndex
          ].parametricEquation = that.getParametricEquation(
            that.option.series[that.selectedIndex].pieData.startRatio,
            that.option.series[that.selectedIndex].pieData.endRatio,
            false,
            false,
            k,
            that.option.series[that.selectedIndex].pieData.value
          );
          // that.option.grid3D.beta = 40;
          that.option.series[that.selectedIndex].pieStatus.selected = false;
        }
        // 对当前点击的扇形，执行选中/取消选中操作（对 option 更新）
        that.option.series[
          params.seriesIndex
        ].parametricEquation = that.getParametricEquation(
          startRatio,
          endRatio,
          isSelected,
          isHovered,
          k,
          that.option.series[params.seriesIndex].pieData.value
        );
        // if (params.seriesIndex === 0) {
        //   that.option.grid3D.viewControl.beta = 100;
        // } else {
        //   that.option.grid3D.viewControl.beta = 40;
        // }
        that.option.series[params.seriesIndex].pieStatus.selected = isSelected;
        // 如果本次是选中操作，记录上次选中的扇形对应的系列号 seriesIndex
        isSelected ? (that.selectedIndex = params.seriesIndex) : null;
        // 使用更新后的 option，渲染图表
        myChart.setOption(that.option);
        that.active = isSelected;
        that.percent = ((that.optionData[params.seriesIndex].y / that.total) * 100).toFixed(0);
        that.linkLegend(isSelected, params.seriesIndex);
        // 改变文字
        if (isSelected) {
          that.topNum = that.optionData[params.seriesIndex].y;
        } else {
          that.topNum = that.total;
        }
      });
      // 监听 mouseover，近似实现高亮（放大）效果
      // myChart.on('mouseover', function(params) {
      //   // 准备重新渲染扇形所需的参数
      //   let isSelected;
      //   let isHovered;
      //   let startRatio;
      //   let endRatio;
      //   let k;
      //   // 如果触发 mouseover 的扇形当前已高亮，则不做操作
      //   if (hoveredIndex === params.seriesIndex) {
      //     return;
      //     // 否则进行高亮及必要的取消高亮操作
      //   } else {
      //     // 如果当前有高亮的扇形，取消其高亮状态（对 option 更新）
      //     if (hoveredIndex !== '') {
      //       // 从 option.series 中读取重新渲染扇形所需的参数，将是否高亮设置为 false。
      //       isSelected = that.option.series[hoveredIndex].pieStatus.selected;
      //       isHovered = false;
      //       startRatio = that.option.series[hoveredIndex].pieData.startRatio;
      //       endRatio = that.option.series[hoveredIndex].pieData.endRatio;
      //       k = that.option.series[hoveredIndex].pieStatus.k;
      //       // 对当前点击的扇形，执行取消高亮操作（对 option 更新）
      //       that.option.series[hoveredIndex].parametricEquation = that.getParametricEquation(startRatio, endRatio,
      //         isSelected,
      //         isHovered, k, that.option.series[hoveredIndex].pieData.value);
      //       that.option.series[hoveredIndex].pieStatus.hovered = isHovered;
      //       // 将此前记录的上次选中的扇形对应的系列号 seriesIndex 清空
      //       hoveredIndex = '';
      //     }
      //     // 如果触发 mouseover 的扇形不是透明圆环，将其高亮（对 option 更新）
      //     if (params.seriesName !== 'mouseoutSeries' && params.seriesName !== 'pie2d') {
      //       // 从 option.series 中读取重新渲染扇形所需的参数，将是否高亮设置为 true。
      //       isSelected = that.option.series[params.seriesIndex].pieStatus.selected;
      //       isHovered = true;
      //       startRatio = that.option.series[params.seriesIndex].pieData.startRatio;
      //       endRatio = that.option.series[params.seriesIndex].pieData.endRatio;
      //       k = that.option.series[params.seriesIndex].pieStatus.k;
      //       // 对当前点击的扇形，执行高亮操作（对 option 更新）
      //       that.option.series[params.seriesIndex].parametricEquation = that.getParametricEquation(startRatio, endRatio,
      //         isSelected, isHovered, k, that.option.series[params.seriesIndex].pieData.value + 5);
      //       that.option.series[params.seriesIndex].pieStatus.hovered = isHovered;
      //       // 记录上次高亮的扇形对应的系列号 seriesIndex
      //       hoveredIndex = params.seriesIndex;
      //     }
      //     // 使用更新后的 option，渲染图表
      //     myChart.setOption(that.option);
      //   }
      // });
      // 修正取消高亮失败的 bug
      myChart.on('globalout', function() {
        // 准备重新渲染扇形所需的参数
        let isSelected;
        let isHovered;
        let startRatio;
        let endRatio;
        let k;
        if (hoveredIndex !== '') {
          // 从 option.series 中读取重新渲染扇形所需的参数，将是否高亮设置为 true。
          isSelected = that.option.series[hoveredIndex].pieStatus.selected;
          isHovered = false;
          k = that.option.series[hoveredIndex].pieStatus.k;
          startRatio = that.option.series[hoveredIndex].pieData.startRatio;
          endRatio = that.option.series[hoveredIndex].pieData.endRatio;
          // 对当前点击的扇形，执行取消高亮操作（对 option 更新）
          that.option.series[
            hoveredIndex
          ].parametricEquation = that.getParametricEquation(
            startRatio,
            endRatio,
            isSelected,
            isHovered,
            k,
            that.option.series[hoveredIndex].pieData.value
          );
          that.option.series[hoveredIndex].pieStatus.hovered = isHovered;
          // 将此前记录的上次选中的扇形对应的系列号 seriesIndex 清空
          hoveredIndex = '';
        }
        // 使用更新后的 option，渲染图表
        myChart.setOption(that.option);
      });
    },
    changePercent() {
      let total = 0;
      this.optionData.forEach(item => {
        total += item.value;
      });
      this.percent = ((this.optionData[this.index].y / total) * 100).toFixed(0);
    },
    // 监听tab点击，更新图表
    monitorClick() {
      const isSelected = this.isActive;
      const k = this.option.series[this.index].pieStatus.k;
      const isHovered = this.option.series[this.index].pieStatus.hovered;
      // 如果之前选中过其他扇形，将其取消选中（对 option 更新）
      if (this.selectedIndex !== '' && this.selectedIndex !== this.index) {
        this.option.series[
          this.selectedIndex
        ].parametricEquation = this.getParametricEquation(
          this.option.series[this.selectedIndex].pieData.startRatio,
          this.option.series[this.selectedIndex].pieData.endRatio,
          false,
          false,
          k,
          this.option.series[this.selectedIndex].pieData.value
        );
        this.option.series[this.selectedIndex].pieStatus.selected = false;
      }
      this.option.series[this.index].parametricEquation = this.getParametricEquation(
        this.option.series[this.index].pieData.startRatio,
        this.option.series[this.index].pieData.endRatio,
        isSelected,
        isHovered,
        k,
        this.option.series[this.index].pieData.value
      );

      this.option.series[this.index].pieStatus.selected = isSelected;
      // 如果本次是选中操作，记录上次选中的扇形对应的系列号 seriesIndex
      isSelected ? (this.selectedIndex = this.index) : null;
      // 使用更新后的 option，渲染图表
      this.chart.setOption(this.option);
      this.active = isSelected;
      this.changePercent();
      // 改变文字
      if (isSelected) {
        this.topNum = this.optionData[this.index].y;
      } else {
        this.topNum = this.total;
      }
    },
    // 联动图例
    linkLegend(active, index) {
      this.$emit('changeLegend', active, index);
    },
    // 求总数
    calculateTotal() {
      const dataArr = this.optionData.map((item) => {
        return item.y;
      });
      this.total = dataArr.reduce((total, item) => {
        return total + item;
      });
      this.percent = ((this.optionData[this.index].y / this.total) * 100).toFixed(0);
    }
  }
};
</script>
<style lang="scss" scoped>
.water-eval-container {
  // width: 9rem;
  height: 100%;
  .container {
    position: absolute;
    z-index: 20;
    transform: translateX(-50%);
    height: 5.6875rem;
    pointer-events: none;
    .child {
      display: flex;
      height: 3.25rem;
      flex-direction: column;
      align-items: center;
      color: #ffffff;
      font-family: "Helvetica-regular";
      .top {
        display: flex;
        // justify-content: flex-end;
        align-items: baseline;
        height: 1.75rem;
        .number {
          font-size: 1.5rem;
          height: 100%;
        }
        .unit {
          font-size: .75rem;
          margin-left: .125rem;
        }
      }
      .bottom {
        height: .875rem;
        font-size: 0.875rem;
        margin-top: 0.25rem;
      }
    }
  }
}
.cityGreenLand-charts {
  height: 100%;
  // width: 9rem;
}
</style>
